Tubular article and method of making the same



May 7, 1940. J, A SALZ 2,200,042

TUBUI'JAR ARTICLE AND METHOD 0F MAKING THE SAME Filed Jan. 11, 1958 D wnunssss INVENTOR 9 H. BY

MM mmm-a y ATTORNEYS *Patented May 7, 1940 PATENT OFFICE:

. TUBULAR ARTICLE AND METHOD F lMAKING THE SAMEv Jacque A. Salz, New York, N. Y.

Application January 11, 1938, Serial No. 184,436

2 Claims.

This invention relates to improvements in tubular members and the method of making the same. n

My invention is particularly applicable to pencil 5 and fountain pen barrels but it should be understood that it may also be applied to the production of other similar tubular articles. In the manufacture of barrels for pencil or fountain pens and similar tubular articles it is frequently desirable that the barrel be provided with an attractive, ornamental design or withv an attractive finished surface. To provide the barrel with the desired design or nish increases the cost of production because it necessitates more costly methods, material or labor.

It is an object of the invention to lovercome these difiiculties and to provide a fountain pen or pencil barrel or similar tubular article having an attractive, ornamental design or an attractractive appearance which heretofore has vbeen confined to the more expensive types of tubular articles.

With these and other objects in mind reference should be had to the accompanying drawing, in which Fig'. l shows a tubular article. made in accordl ance with my invention;

Fig. 2 is a longitudinal, sectional view of the article;

Fig. 3 shows another tubular article made in accordance withA my invention, with portions thereof broken away so as more clearly to disclose the construction;

' Fig. 4 is a sectional view on the line 4-4 of Fig. l;

Fig. 5 is a Fig. 1;

Fig, 6 is a'vew of a shell of the type used in sectional view on the line 5 5 of forming the outerv surface of a tubular article made in accordance with my invention; and

.Fig.'7 is alongitudinal, sectional View of a die which may be employed in carrying out my inventlon In the manufacture of tubular articles such as penciland fountain pen barrels it is desirable t'ohave an attractive, ornamental design on the surface thereof or to employ an attractive, ornamental material such as the material which is known as pearl in the trade. Tubular articles tive finished surface but which is nevertheless tubular `articles having an ornamental and at- I of this character have heretofore been relatively expensive and accordingly could not be employed to advantage in inexpensive fountain pens, pencils and the like.

In carrying out my invention I employ a tubu- I 5 ,larshell having the same external diameter as the desired tubular article but having a relatively thin Wall. By placing the shell in a die and depositing plastic material on the inner surface thereof and, if desired, at one or both ends therev10 of a tubular article of the desired thickness and' size can .be produced. The distinctive nish or ornamentation of the shell however is preserved as the outer surface of the barrel. f

As a specific example of one method of carryl1p; ing out my invention, in the accompanying drawing a tubular shell made of pearl is illustrated at Il. As shown most clearly in Fig. l the shell has an attractive mottled ornamentation thereon and is characterized by a distinctive, at- `20 tractive, finished surface. The material knowni" as pearl in the trade is a thermo-plastic material. similar to pyroxylin, cellulose acetate or the like. 'It should be understood that in carrying out my invention a shellv of any material having the desired ornamentation or appearance may be 25 employed, although the best results are obtained byernploying thermo-plastic materials such as cellulosel acetate, pyroxylin, or cellulose nitrate.

The shell Il) illustrated in the accompanying drawing is of the same external diameter as the rE30 finished barrel 9 which it is desired to produce. However, its wall thickness is considerably less thanthat of the' desired finished barrel. The barrel or other tubular article 9 is produced by depositing a layer of plastic material on the in- 35 ner surface of the shell as indicated at I I, which may be extended laterally from` one or both ends of the shell as indicated at I2. The layer of plastic material is of such a thickness as to produce a barrel of the desired strength and thickness. v4:0 The plastic material which is thus deposited is preferably a thermo-plastic material such as celv lulose acetate, pyroxylin, or cellulose nitrate and is deposited on the shell in plastic condition, preferablyin a die or mould. 445

One Aform of die which may be used in thus forming the barrel is shown at I3 in Fig. 7 and is provided with a die cavity I4 formed in the desired shape and size of the barrel. At ther righthand side as viewed in Fig. 'l a stripping 50l hand end of the cavity I4 as viewed in Fig. '7 communicates through a tapered opening I'I with a nozzle I8 having communication with the source of supply of the thermoplastic material employed in making the barrel.

In making the barrel or other tubular member, the shell I0 is placed in the die cavity I4. If it is desired that the shell extend the entirev length of the barrel it should extend the entire length of the cavity. In the illustrated embodiment the shell is not as long as the finished barreliand accordingly it is somewhat shorter than the die cavity. The thermo-plastic material is heated so that it is in workable or plastic condition and it is then introduced under relatively high pressure through the nozzle IS into the die cavity I4 where it is forced around the core I6 and inside oi the shell 60 which has relatively tight engagement with the walls of the die so as to prevent any of the material from entering between the die and the outer stuiace of the shell. It will be appreciated that the thickness of the barrel wall is determined by the space between the core and the cavity walls and the thickness Of the` barrel may be varied by varying-the diameter of the core. The thermo-plastic material being in plastic condition at the time it enters the die forms close and intimate engagement With the shell l. It is then permitted to set or harden and this action may be hastened by airor watercooling the die. As the plastic material Sets or hardens it adheres to the shell It). When the shell iii is made of a thermo-plastic material the entering heated plastic material at rst renders the inner surface of the shell plastic or workable and when the barrel s ets or hardens it forms a unitary structure with definite cohesion between the shell and the `thermo-plastic material deposited thereon. When the barrel has properly set or hardened the plate i5 and core I6 are drawn away from the die and the core I5 is then drawn through the stripping plate to release the barrel from the core. It should be understood however, that the die that is illustrated and describedr in connection with this method forms no part of this invention but is merely one Well known form of die which may be employed in' carrying out my method.

The shell IIJ may extend the entire length of the tubular article, or, as shown herein, may extend only a portion of the length of the article,

and in the latter case the remainder of the length of the article is formed entirely of the thermoplastic material. This is most clearly illustrated in Figs. 21, 4 and 7, wherev the portio-n of the thermo-plastic material extending beyond the shell IIl is indicated by the numeral I2. It will be seen that the material at vthe point I2 is preferably equal to the combined thickness of the shell IB and layer of thermo-plastic material II.

The tapered projecting end I9 which is'shown at the end of the barrel results from the shape of the inlet to the die cavity and may be removed fr'om the article when it is formed into a fountain pen barrel or pencil barrel or the like.

in Fig. 3 I have illustrated another use to which my invention maybe applied. Thus, a metal band Z may be formed around and embedded in a barrel by means of the method herein described. In accomplishing this result the band Ell is placed in the die in the same manner as the shell Ill, and the thermo-plastic material is unitary mass.

deposited through the nozzle I8 into the die cavity, forming intimateA engagement'with ,theband The thermo-plastic material is then caused to set or harden and is removed from the die. It

should be understood however, thatwhile my invention may be employed in applying metallic l or other ornamentations to a barrel it is particularly suited to the production from plastic materials of tubulararticles such as penciland pen barrels, particularly articles` of this character having an attractive finish or ornamentation. When a shell of a plastic material such` as indicated at il! is thus employed in forminga barrel, a unitary structure in which the several parts have close cohesion is produced. It Will thus be seen that by means of my invention an improved tubular article, particularly a `fountain pen or pencil barrel having an attractivefornamental appearance and of rugged', durable construction is produced at a minimum` of expense.

t should be understood that modiiications' may be made in the illustrated and described embodiment of my invention without departing from the invention asset forth in the accompanying claims. term fountain pen or pencil barrel as used herein means not only the bodyportion of a pencil or pen but also the cap. f

l. rIhe method of orminga tubular articl such as a fountain pen or pencil barrel having a pearl finish which comprises first providing a 'thin tubular shell of a plastic pearl material composed of a cellulose derivative and having an attractive ornamental outer surface, the shell having ".55

It should also be understood that thelg an external diameter equal to the 'external dj ameter of the member to beiormed, rendering workable and uid by heat a mass of thermoplastic material composed of a'cellulose' derivative which is relatively less expensive than the material of the shell, placing the rshell in a die provided with a bore of substantially the same internal diameter as the external diameter. of

l the shell but of greater length, ithe die being provided with a centrally disposed 'mandrel closing one end of the die and' passingaxially of the shell, forcing the'heated'iiuid mass of thermoplastic material through the other end of the die and lling the space between the die, mandrel and shell, the temperature of the uidthermo- *50 plastic being such that the surfaces of the shell which are exposed to the heated thermoplastic material will become plastic and fuse with the," contacting therni'oplastiol material, then permit-j ting the thermoplastic material tol harden 'by' cooling so that the fused contacting surfacesA of the shell and material'will form a'homogeneous hardened mass.

2. A barrel for fountain pens or theI like comprising a molded hollow'body formed of thermoplastic material, -a thin tubular shell embracing part of the body and formed of a plastic pearl material composed of a cellulose derivative andr relatively more expensive `than the material forming the hollow body, the shell forming an ornamental outer lsurface which is flush with the outer surfaceof thatpart of the body which y projects beyond .the shell, the inner wall jof the shell and the Wall of the body which is con'ned Withinfthe shell being -fused into a homogeneous 17.@

l JACQUE A. sALz. l 

